Computerized spreadsheets are widely used for organizing numerical and textual data in such environments as accounting, financial/investments, inventory, and the like. The spreadsheets consist of rows and columns of individual cells. The columns are organized by letter--Columns A, B, C, etc.--and the rows are organized by number--Rows 1, 2, 3, etc. Each cell is identified by a combination of column letter and row number. Cell "B3," for instance, is in column B and row 3. Numerical and textual data are entered into the cells of the spreadsheet according to the organization imposed by the author. The cells can be formatted to present the numbers and text in a desired appearance.
Conventional spreadsheets also permit an author to define mathematical functions within individual cells. The functions are set apart from normal data by use of a leading descriptor entry, such as an "=" sign. It is common for the mathematical functions entered in one cell to use data contained in other cells. The function itself is not displayed in the cell; rather, the cell displays the results of the function.
To perform calculations on the data entered into the spreadsheet, the author has to explicitly define the function and enter it in one of the cells. One typical spreadsheet example is to sum all of the numbers in a column. The author selects a cell in the spreadsheet which will be used to show the summation, and in that cell, defines a summation function which adds the values of the particular cells in the column. To compute the summation of numbers residing in cells B3 to B12 and show that sum in cell B13, the author enters in cell B13 one of the following equations: EQU =SUM(B3:B12) EQU =B3+B4+. . .+B12+B13
Notice that the function begins with the "=" descriptor to identify that the cell contains a function, and not text or numerical data.
For commonly used equations, spreadsheets typically have a predefined list of functions from which the author may choose. The list can be presented in a pull-down menu, or the like. The author simply chooses a particular cell and selects a function from the predefined list. The spreadsheet enters the selected function into the chosen cell, so that the author does not have to type in the function. In addition to predefined lists, one present-day spreadsheet marketed under the name Excel by Microsoft Corporation offers a "function wizard" which guides the author step-by-step through the parts of a function to ensure entry of the appropriate cell information and parameters. While the predefined lists and function wizards provide shortcuts to improve operation efficiency, they too result in entry of a function within a designated cell.
There are occasions, however, when an author only wants a quick, temporary calculation that is not intended to be part of the workbook. For instance, the author might wish to know the subtotal of a group of cells, or to analyze data within a set of cells to find a subset of those cells which produce a certain value. With conventional spreadsheets, the author is forced to enter the formula in a cell (either by entering the function, selecting one from a menu, or using a function wizard), view the result, and subsequently go back and delete the function from the cell to remove it from the workbook.
Accordingly, there is a need to improve computerized spreadsheets to handle intermediate calculations without having to enter formulas into the worksheet.